There are two types of electronic pantograph available in Japan. One type is made in the United States (D instrument), and another type is made in Japan (H instrument) . Measuring accuracy of these types of electronic pantograph was compared in this study. Each of D instrument and H instrument was attached to the same semi-adjustable articulator, respectively, and the difference between the set values of the articulator and the output values of the electronic pantographs were obtained and evaluated. The results are summarized as follows:
1. Concerning the measuring accuracy for sagittal condylar path inclination, the S. D. obtained from H instrument was three times and one-half smaller than that obtained from D instrument.
2. H instrument resulted in the better measuring accuracy regarding the absolute values of the immediate side shift in comparison with D instrument. And, the S. D. of the date obtained from H instrument was 1.7 times smaller than that obtained from D instrument. Further, it was judged from the eye measurement that H instrument was superior to D instrument concerning the graphic displays of the horizontal lateral condylar paths.
3. As for the measuring accuracy for progressive side shift, the S. D. obtained from H instrument was one and one-half times smaller than that obtained from D instrument when the sagittal condylar path inclination of the anticulator was fixed to 30 degrees. The output data regarding the progressive side shift obtained from D instrument altered in combination with the changes of sagitttal condylar path inclination although the progressive side shift of the articulator was fixed to the constant value.
4. Abnormal data regarding sagittal condylar path inclination and progressive side sift were observed for D instrument.
5. It may be concluded that the measuring accuracy of H instrument was 2.3 times better than that of D instrument when abnormal data were excluded. If those abnormal data were included, the measuring accuracy of H instrument was five times better than that of D instrument.
6. A couple of reasons may be pointed out concerning the difference of the measuring accuracy between those two types electronic pantographs. The sensor of H instrument is non-contact type, while that of D instrument is contact type. Obviously, non-contact type of sensor results in the better measuring accuracy.
Computer calculations are achieved in H instrument system so that movement of the center of condyle is obtained, While D instrument simply displays the results of measurement obtained outride of the face and calculations for obtaining the real movement of the center of condyle does not seem to be realized.

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Three dimensional orbits of maxillary incisal point, mesiolingual cusp of the first molor, and the center of the condyle during protrusive, left lateral and right lateral movements of the articulator were obtained by means of computer calculation. The results are as follow:
1. Saggital condylar path inclination has a great effect upon the morphology of the molar cusps. There is a tendency that the greater the sagittal condylar path inclination is, the steeper the cuspal inclination becomes, and the gothic arch angle also gets greater.
2. Progressive side shift and the Bennett angle have less effect upon the morphology of the molar cusps compared with saittal condylar path inclination. However, those effects cannot be ignored totally.
3. The distance between the centers of the condyles has as much effect upon the morphology of the molar cusp as progressive side shift has.
4. Immediate side shift has a great effect upon the morphology of the molar cusps and its effect is as great as, the sagittal condylar path inclination. From the quantitative analyses in this study, the fact that the significance of immediate side shift had been pointed out in Gnathology proved to be right.
5, Quantitative analyses concerning the effect of each factor of the condylar path upon the morphology of molar cusps were performed. According to the results, three degrees of sagittal condylar path inclination, six degrees of the Bennett angle and progressive side shift, 10 mm of the distance between the centers of the condyles, and 0.1 mm of immediate side shift during lateral movement are equally effective when 0.09 mm³ground volume is equivalent.
6. From the quantitative analyses mentioned above, comparative effectiveness of each factor of condylar path upon morphology of the molar cusps were measured. The results indicated that sagittal condylar path inclination and immediate side shift are equally effective and that progressive side shift, the Bennett angle and the distance between the centers of the condyles are approximately one-fourth as effective as sagittal condylar path inclination and immediate side shift.

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The purpose of this study was to measure and to analyze the form and the size of human maxillary triangle. Furthermore, the designs regarding to the intercondylar distance of the articulators were evaluated in comparison with those of the human maxillary trianle.
30 Japanese adults, consisting of 15 males and 15 females, with ages ranging from 20 to 40 were selected. The qualifying criterion was that their maxillomandibular relation be orthognathic.
Prior to the measurements of maxillary triangle, hinge axis location and hinge bow transfer, were performed.
The distance between left and right stylus and the distances between left stylus and right stylus and maxillary incisal point were determined with the measuring device.
The results of measurement were summarized as follows.
1. The average face width of the male group was 15.3 cm. The average distance of skin to incisal point was 12.4 cm on the right and 12.3 cm on the left.
2. The average face width of the female group was 14.4 cm. The average distance of skin to incisal point was 11.6 cm on the right and 11.3 cm on the left.
3. The average face width of 30 adults was 14.9 cm. The average distance of skin to incisal point was 12.0 cm on the right and 11.8 cm on the left.
Based on those results, maxillary triangles of the group was obtained by subtracting 4.6 cm from the facial width. The distance of condylar point to incisal point was determined by geometrical means.
4. According to the results, the average intercondylar distance of the male group was 10.7 cm. The average distance of condylar to incisal point was 11.1cm on the right and 11.1 cm on the left.
5. The average intercondylar distance of the male group was 9.8cm. The average distance of condylar to incisal point is 10.3 cm on the right, and 10.1 cm on the left.
6. The average intercondylar distance of all the group was 10.3 cm, the average distance of condylar to incisal point is 10.7 cm on the right, and 10.6 cm on the left.
7. The shape of maxillary triangle was considered to be isosceles triangle, however, definite conclusion concerning the average size and shape of human maxillary triangle could not be made due to lack of the number of the group. Tremendous number of the group may be needed for this type of study.
8. The intercondylar distance of articulator most suitable to provide was 10.5 cm as far as the anatomical mean value of intercondylar distance was concerned.

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Not much study has been reported concerning the clinical application of occlusal sound for examination and diagnosis of occlusion. Stewart (1953), Thompson (1954), Schwontz (1959), and Silverman (1962) stdied the tooth contact sounds and the TMJ sounds by means of the stethosope or by directly listening to those. Those me thods, however, did not provide reliable results for they did depend entirely upon the listener's auditory sense.
In order to analyze the occlusal sounds in much objective manner, Watt (1967) and Brenman (1972) developed the new methodslogy, of which the visual records of sound of occlusion was possible. Occlusal sound was picked from the bone transmission sound by microphone and was transduced to the electrical signals and displayed on the magnetic oscilloscope or Braun tube oscilloscope. Figures displayed may be stored in the pen-recorder or pictured. Brenman (1972) developed occlusograph being applicable for occlusal analysis in clinical dentistry.
Several studies have been reported concerning the occlusal sounds on the Japanese journals of prosthodontics or other dental associations since 1960s. Author developed two types of the occlusal sound wave detector, namely DENTAL sound CHEKER 201 and 202, in 1976 and 1977, respectively. In those detectors, Occlusal sound wave was picked by the microphone, and the amplitude, duration, dispanity in impact time and so on, were observed so as to examine stability of tooth contact.
In spite of excellent clinical performance of the occlusal aound wave detecter, there still are a few problems such as the obscrity or the resonance of the sounds through the body structure. This article dealt with the analysis of the occlusal sound waves displayed on the detector.

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When many teeth are restored, restoration must always be matched with each organ and must show ideal function. however, by the time restoration is completed, various elements have added concerning accuracy. In other words, tiny error will be accumulated in the process from impression to restoration which will finally cause a big error. The remounting removes those accumulated errors in each of these processes. Author with to introduce a modified Thomas remounting technique.

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Methods of occlusal diagnosis for oral rehabilitation were discussed. Among the methods, one employing articulator has been popular for a long time. Krough-Poulsen's palpation became popular rather recently. And now, functional occlusal diagnosis employing Dental Electronic apparatus including dental sound checker and Mandibular kinesiograph are available.
Further, standardization of TMJ radiographs provides access for using them in occlusal diagnosis. These old and new methos are not effective by itself, but helpful for occlusal diagnosis when the result of each method were comprehended and combined thoroughly.
This report dealt with the knowledges and techniges being necessary to operate those methods so that the dentists can use those as proper diagnostic means for determining occlusion.

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